In the context of climate change, the study of the variability of the climatic extremes in several regions of the world is of capital importance. This study has as main objective to analyze the variability of extreme ...In the context of climate change, the study of the variability of the climatic extremes in several regions of the world is of capital importance. This study has as main objective to analyze the variability of extreme temperature events in the Beninese basin of the Niger River for the recent and the near future. To achieve this objective, seven (07) extreme temperature indices based on historical daily temperature observations (1976 to 2019) and REMO RCM simulation outputs of RCP4.5 and RCP8.5 scenarios (2021-2050) were calculated. The obtained results were represented by calculating the means for each index and analyzing the trends and their significance by the Mann-Kendall method. The results show that the indices of extreme temperature intensity (TNn, TXx, and DTR), and those related to the frequency of warm sequences (WSDI, TN90p and TX90p) have experienced a significant increase in the past. This increase will continue until 2050. In contrast, the cold sequence frequency index (CSDI) decrease over the historical period as well as over the future period. These indices show much more change with the RCP8.5 scenario than with the RCP4.5 of the REMO climate model. Only the TXx and CSDI indices show statistically significant changes at all stations.展开更多
In a world of increasing resistance to current antibiotics,search of novel therapeutic options is urgently needed.The aim of this work was to screen plant crude extracts for direct or indirect(inhibition of resistance...In a world of increasing resistance to current antibiotics,search of novel therapeutic options is urgently needed.The aim of this work was to screen plant crude extracts for direct or indirect(inhibition of resistance)antimicrobial activity.Four crude extracts from 12 plants traditionally used in Benin for the treatment of infections were展开更多
About 80%of population in developing countries use traditional remedies in their usual health care and plants used in traditional medicine are an interesting alternative to expensive and hardly available modern medici...About 80%of population in developing countries use traditional remedies in their usual health care and plants used in traditional medicine are an interesting alternative to expensive and hardly available modern medicines,mainly in rural areas.Moreover,they are a promising source of new drugs structurally innovative.Therefore it is important to investigate their biological properties and we focused on5 beninese plants:Byrsocarpus coccineus Schumach.&Thonn(Connaraceae),Carpolobia lutea G.Don(Polygalaceae),展开更多
The coastal zone of Benin is inherited from the last marine oscillations of the Quaternary. A rich and very fragile environment, it presented until the 1960s, a shoreline in dynamic equilibrium over the entire 125 km ...The coastal zone of Benin is inherited from the last marine oscillations of the Quaternary. A rich and very fragile environment, it presented until the 1960s, a shoreline in dynamic equilibrium over the entire 125 km of coastal line. Since the 1960s, with the construction of important development infrastructures (ports, dams, groins), the Beninese coast is now subject to risks of coastal erosion and seasonal flooding due to the overflow of lagoon water bodies. The present study, based on socio-economic surveys in the communes of Ouidah, Comè and Grand Popo, exposes the extent of coastal risks and socio-economic and environmental damage in the southwestern coastal zone of Benin. The results show that in terms of land, 2.9 ha and 5.7 ha of land have been permanently lost to coastal erosion in the communes of Ouidah and Grand Popo respectively. Similarly, 212 ha of crops of all types were affected by the flooding, including 35 ha destroyed, i.e. 6.67 ha, 11.3 ha in Comè, 4.67 ha Ouidah and 14 ha Grand Popo. Also, 6435 buildings were affected, and 4235 huts were damaged. In addition, working tools, food stocks and other items are counted among the losses recorded by coastal hazards with their corollaries of diseases. The cost of losses and damages in the 08 districts amount to 418,000,000f cfa of which 266,000,000f cfa of damage and 152,000,000f cfa of loss.展开更多
In the context of a changing climate,the Beninese Niger River basin has been the focus of several research studies for the quantification,planning,and modeling of water and related resources for sustainable use.This r...In the context of a changing climate,the Beninese Niger River basin has been the focus of several research studies for the quantification,planning,and modeling of water and related resources for sustainable use.This research aims to characterize the historical(1976-2019)and projected(2021-2050)hydrological drought of the Beninese Niger River basin.The study used daily observations of rainfall,maximum and minimum temperatures,runoff rates and simulations of HIRHAM and REMO RCMs from fifteen(15)rainfall stations installed around the basin.It uses standardized streamflow indices(SDI)at 12-month and 36-month time steps.The results show that the calculated SDI indices show,on average,for all the model scenarios used,chronological trends of increase.These increases are not significant(are of the order of 0.00001 per year).The analysis of the SDI indices shows that,on average,the hydrological droughts in the Beninese basin of the Niger River will increase at 36 months and decrease at 12 months of the SDI.In fact,these small variations of hydrological droughts will be accompanied by the increase of their duration and the decrease of their magnitudes.The droughts detected in the Benin basin of the Niger River during the historical period will continue until 2050 in the same range but with more extended drought lengths.It should be noted that most of the changes observed in the calculated and analyzed indices are not significant.展开更多
文摘In the context of climate change, the study of the variability of the climatic extremes in several regions of the world is of capital importance. This study has as main objective to analyze the variability of extreme temperature events in the Beninese basin of the Niger River for the recent and the near future. To achieve this objective, seven (07) extreme temperature indices based on historical daily temperature observations (1976 to 2019) and REMO RCM simulation outputs of RCP4.5 and RCP8.5 scenarios (2021-2050) were calculated. The obtained results were represented by calculating the means for each index and analyzing the trends and their significance by the Mann-Kendall method. The results show that the indices of extreme temperature intensity (TNn, TXx, and DTR), and those related to the frequency of warm sequences (WSDI, TN90p and TX90p) have experienced a significant increase in the past. This increase will continue until 2050. In contrast, the cold sequence frequency index (CSDI) decrease over the historical period as well as over the future period. These indices show much more change with the RCP8.5 scenario than with the RCP4.5 of the REMO climate model. Only the TXx and CSDI indices show statistically significant changes at all stations.
文摘In a world of increasing resistance to current antibiotics,search of novel therapeutic options is urgently needed.The aim of this work was to screen plant crude extracts for direct or indirect(inhibition of resistance)antimicrobial activity.Four crude extracts from 12 plants traditionally used in Benin for the treatment of infections were
文摘About 80%of population in developing countries use traditional remedies in their usual health care and plants used in traditional medicine are an interesting alternative to expensive and hardly available modern medicines,mainly in rural areas.Moreover,they are a promising source of new drugs structurally innovative.Therefore it is important to investigate their biological properties and we focused on5 beninese plants:Byrsocarpus coccineus Schumach.&Thonn(Connaraceae),Carpolobia lutea G.Don(Polygalaceae),
文摘The coastal zone of Benin is inherited from the last marine oscillations of the Quaternary. A rich and very fragile environment, it presented until the 1960s, a shoreline in dynamic equilibrium over the entire 125 km of coastal line. Since the 1960s, with the construction of important development infrastructures (ports, dams, groins), the Beninese coast is now subject to risks of coastal erosion and seasonal flooding due to the overflow of lagoon water bodies. The present study, based on socio-economic surveys in the communes of Ouidah, Comè and Grand Popo, exposes the extent of coastal risks and socio-economic and environmental damage in the southwestern coastal zone of Benin. The results show that in terms of land, 2.9 ha and 5.7 ha of land have been permanently lost to coastal erosion in the communes of Ouidah and Grand Popo respectively. Similarly, 212 ha of crops of all types were affected by the flooding, including 35 ha destroyed, i.e. 6.67 ha, 11.3 ha in Comè, 4.67 ha Ouidah and 14 ha Grand Popo. Also, 6435 buildings were affected, and 4235 huts were damaged. In addition, working tools, food stocks and other items are counted among the losses recorded by coastal hazards with their corollaries of diseases. The cost of losses and damages in the 08 districts amount to 418,000,000f cfa of which 266,000,000f cfa of damage and 152,000,000f cfa of loss.
文摘In the context of a changing climate,the Beninese Niger River basin has been the focus of several research studies for the quantification,planning,and modeling of water and related resources for sustainable use.This research aims to characterize the historical(1976-2019)and projected(2021-2050)hydrological drought of the Beninese Niger River basin.The study used daily observations of rainfall,maximum and minimum temperatures,runoff rates and simulations of HIRHAM and REMO RCMs from fifteen(15)rainfall stations installed around the basin.It uses standardized streamflow indices(SDI)at 12-month and 36-month time steps.The results show that the calculated SDI indices show,on average,for all the model scenarios used,chronological trends of increase.These increases are not significant(are of the order of 0.00001 per year).The analysis of the SDI indices shows that,on average,the hydrological droughts in the Beninese basin of the Niger River will increase at 36 months and decrease at 12 months of the SDI.In fact,these small variations of hydrological droughts will be accompanied by the increase of their duration and the decrease of their magnitudes.The droughts detected in the Benin basin of the Niger River during the historical period will continue until 2050 in the same range but with more extended drought lengths.It should be noted that most of the changes observed in the calculated and analyzed indices are not significant.
